I think Unity can distribute their runtime library via CDN (just like three.min.js or something). It will able to cut down the initial some megabytes.
Progressive downloading technique (like AssetBundle) is a must for both loading time and server costs. Every developer should use it because if many games have massive long loading time (like Epic Citadel or BananaBread or Monster Madness. Whatever Mozilla says, these demos are not commercial ready), end-users will hesitate to click game links. I feel many gamers already stopped considering the web as a game platform these days. Kids know how to download games from App Store, but they don't know how to use Mobile Safari. All App Store, Google Play and Steam are growing. Many users will continue to prefer download apps for a long time.
Ultimately, time may solve the problem. The internet bandwidth is growing 50% per year. Many PC browser games will start instantly 5 or 10 years later, Mobile will have more trouble.
Progressive downloading technique (like AssetBundle) is a must for both loading time and server costs. Every developer should use it because if many games have massive long loading time (like Epic Citadel or BananaBread or Monster Madness. Whatever Mozilla says, these demos are not commercial ready), end-users will hesitate to click game links. I feel many gamers already stopped considering the web as a game platform these days. Kids know how to download games from App Store, but they don't know how to use Mobile Safari. All App Store, Google Play and Steam are growing. Many users will continue to prefer download apps for a long time.
Ultimately, time may solve the problem. The internet bandwidth is growing 50% per year. Many PC browser games will start instantly 5 or 10 years later, Mobile will have more trouble.